The objectives of this study are to identify optimal pH range for root function and minimize root turnover on HLB-affected rootstocks and how uneven pH levels in the root zone (e.g. irrigated vs. row middle portions of root system) affect the overall health of the tree. This is being done in a split root system in the greenhouse where pH of different parts of the root system can be controlled an maintained. We have completed construction of the rhizotrons and split the roots of and transplanted trees into the rhizotrons. Part of the delay was because we constructed new Aluminum framed rhizotrons with hollow framing to allow easy collection of irrigation leachate for nutrient analysis. This will also allow them to be sterilized and reused in the second rep without the risk of the frames rotting before the end of the experiment, which became a problem with the wood frames used in prior experiments. The trees for the first rep of the experiment will be inoculated within the week and irrigation water treatments will begin.